1. Field
The invention relates to electrical connectors.
2. Discussion of Related Art
Electrical connectors are used to provide a separable path for electric current to flow between components of an electrical system. In many applications, numerous connections between components can, in turn, require numerous signal and/or power connections within a given electrical connector. Lately, there has been an increase in the number of connections required for typical electronic components, and an increase in demand for greater numbers of electrical connections in electrical connectors. There has also been a general reduction in the size of electronic components, which has created demand for smaller electrical connectors. For either of these reasons, there is a need for electrical connectors with increased current density, where “current density” refers to the amount of current passed through a given connector divided by the area of the connector, along with a higher density (area density or line density) of smaller contacts. Some of these electrical connectors are required to handle as much as 5 to 20 amps per connection within the connector. Existing technologies cannot meet these requirements while also providing reliable electrical connections.
Applicants also appreciate that in many applications, particularly those involving small conductors, it can be desirable to maximize the contact area between a conductor and a mating element. Connectors with conductors that make contact over a larger area or that produce multiple contact points per connection can often support greater amounts of current flowing through the connector, and in doing so can provide connectors that can support an increased current density.
Greater contact forces can provide for a more reliable electrical connection by preventing separation of the conductor and mating element. Additionally, higher normal contact forces can cause wiping action between the conductor and the mating element when they are engaged in a sliding manner. This wiping action can help remove debris that might be on the conductor or mating element, which might otherwise reduce the reliability of the connection. Wiping action can also help break oxide layers that can limit conductivity.
Many materials and design problems are exacerbated at small size scales. Connectors with many small electrical contacts are generally more susceptible to damage during handling due to the fragility of the small contacts. Some known small-scale connectors that incorporate solder balls may experience increased failure due to solder ball cracking. Additionally, some known connectors that employ small-scale “arm” contacts protruding from a body of the connector may be easily damaged during handling. Materials and designs of electrical connectors with a high density of small contacts must maximize conductivity while maintaining sufficient contact forces, maintaining sufficient resistance to stress relaxation and creep, and maintaining sufficient durability for handling purposes.